Markdown docs
Markdown is great for stable human-readable material: specs, runbooks, API notes, and long explanations. Markdown is weak when agents need to know which facts are current, which decisions govern the work, what belongs to what, and what changed during the last session. Product Brain complements Markdown by turning durable product knowledge into connected entries with governance.Wikis and Notion
Wikis are useful for discovery and explanation. They are not usually the place an agent checks before touching code, planning a feature, or resolving a product tension. The Chain is designed for that moment of work. It is smaller, more structured, and connected to the task at hand.Built-in agent memory
Agent memory is getting better fast. It already remembers facts across sessions, and team-shared memory is coming from every major provider. The capability gap is closing. But storing a fact is not the same as governing it. Agent memory can remember “we use feature flags.” It cannot know that decision governs the onboarding work package, which is blocked by an open tension, which was informed by an insight about user drop-off. It cannot tell you whether the decision is still current or has been superseded. It cannot enforce that the next agent must respect it before touching code. Memory stores facts. The Chain stores provenance: the typed relationships that trace how a product position was reached and whether it still holds. That distinction matters more as memory gets better, not less.When to use each
- Use Markdown for long-form explanation.
- Use a wiki for human browsing and company reference.
- Use agent memory for facts and preferences a provider can remember for you.
- Use Product Brain for product truth that needs provenance, authority, and relationships agents must respect.